Brand-new dad Neil Patrick Harris is still getting used to his newborn twins -- and their distinct gastrointestinal issues.
He and his partner David Burtka welcomed son Gideon Scott and daughter Harper Grace via surrogate six weeks ago.
The little boy, he said Monday on CBS' "The Talk," is "a great burper! ... Babies, they can burp!" the "How I Met Your Mother" actor, 37, gushed. "I've never been happier."
Gideon "sleeps all the time," but little Harper is "fussier," he said, explaining that she suffered from "some sort of lower G.I. [problem]...she's always working through something."
"It feels awful," he admitted. "All you want as a parent is to make sure they're okay and that they're comfortable."
He and Burtka tried a hypoallergenic formula and then finally consulted with an ostopath -- which did the trick.
"It was fantastic," the star said. "[Harper] sort of snapped and was a different person. Super calm. Everything is much better."
He and his partner have warmed up to one parenting practice: swaddling.
"Swaddling, we thought, was ridiculous," he admitted before learning to love swaddle time with his little ones.
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